Roasting apparatus for roasting a variety of materials including fresh or green coffee beans is known. The taste and fragrance of coffee depend largely on how and the degree to which the coffee beans have been roasted and how quickly, following roasting, the beans are consumed by brewing coffee with them. It is desirable to produce roasted coffee beans that are consistent in taste and fragrance and in a manner that minimizes storage times to optimize the taste of fresh coffee.
Presently, to ensure proper roasting, an experienced roastmaster commonly roasts green coffee beans at a central location for distribution to multiple destinations for sale and consumption.
Since coffee beans are presently roasted at a central plant for sale at multiple retail locations, such as supermarkets, stores, and specialty shops, as well as coffee and espresso bars, the roasted beans must be stored and shipped before they reach the consumer. This is in and of itself time-consuming and costly. In addition, for cost and transportation reasons it is not feasible to effectively distribute coffee that is roasted on a given day for sale at the various retail establishments on the same day. Thus, coffee beans presently for sale at retail establishments are seldom fresh and, typically, they are several days to several weeks old before they reach the consumer. This compromises the quality, and especially the aroma, of the coffee and, additionally, increases its cost because of the need to make relatively many deliveries from the roasting plant to the retail locations. Attempts to retain the freshness of roasted coffee beans by, for example, placing them in vacuum bags following roasting do not in fact materially prolong the shelf life of the coffee beans or prevent a deterioration of their aroma if the roasted beans are stored for any length of time before they are consumed.
Present-day roasting techniques have additional problems. Since roasting takes place at relatively high temperatures, typically in the vicinity of about 500° F. (about 260° C.), large amounts of smoke and other byproducts are generated, such as white plume smoke, hydrocarbons, and volatile organic compounds (“VOCs”) that pollute the atmosphere unless the exhaust gases are first cleaned. This requires an expensive and energy-consuming afterburner that is normally built into the exhaust gas stack for the roasting machine extending through the surrounding wall or ceiling so that the vented exhaust gases are reasonably clean and non-polluting.
The installation and maintenance of exhaust gas venting and scrubbing equipment is relatively expensive and requires modifications to the building. As a result, roasting coffee at individual retail locations has not previously been seriously considered. Instead, the equipment is installed in a few, relatively large roasting plants where the associated costs can be amortized over a relatively large volume of beans that is being roasted for distribution to and sale at many retail locations. Roasting coffee beans at individual retail locations is further unfeasible because of the need to have the roasting process supervised by an experienced roastmaster. The daily roasted coffee bean sales volume is typically too small to justify the high cost of a roastmaster.
As a result of all the foregoing, coffee is today roasted and distributed in practically the same manner as this was done for a very long time. However, the taste and aroma of coffee beans would be greatly improved if it were possible to roast the beans efficiently at the point of sale to the consumer, rather than at a remote, central plant, and the cost of coffee would be reduced if the need for a roasted coffee bean distribution system could be eliminated and coffee beans could be roasted without the supervision of an experienced roastmaster. The cost of coffee to the consumer could then be decreased and/or the profit margin for the coffee roaster and retailer could be increased.
The present invention, as further described below, achieves these goals while assuring a constant, uniform roasting of the beans, resulting in the desired constant and uniform aroma.